First Appearance of Catwoman, Batman Comics #1 Spring 1940

"Quiet or Papa spank."

Hiding aboard a cruise ship in plain sight, Catwoman/Selina Kyle uses a disguise device very similar to that of the character played by Kay Francis in the 1935 film "I Found Stella Parish" in which an actress hides aboard a cruise liner to America by dressing as an elderly lady.

In this Bill Finger story from Batman #1, Spring 1940, with Bob Kane and Jerry Robinson artwork, Selina Kyle is a black-haired female burgler who ends up escaping before the end, much to the obvious delight of Batman who doesn't try very hard to bring her into custody of the police (to the confusion of Robin).